Biosensors, arrays potentiometric

Two possible architectures for TFT-addressed biosensor arrays are illustrated in Figs. 6.10 and 6.11. For potentiometric sensing, the biosensing pad is connected to the gate of the TFT (see Fig. 6.10), which acts as the transducer. A dummy transistor, where no biomolecular interaction occurs, can be used for differential measurements [45]. For current detection, the sensing pad needs to be connected to the source or the drain of the TFT as shown in Fig. 6.11. 

In the next step of complexity, and also in the proper conceptual idea of BioETs, I will include the design of analysis systems with biosensor arrays incorporating one-enzyme biosensor and, as the rest of sensors in the array, conventional type potentiometric or voltammetric sensors. With this conceptual design, the application normally performed is the determination of a specific substrate or group of substrates in presence of interferents. 

Urea plus alkaline ions Array of potentiometric sensors and biosensors Urine [75]... 

Perhaps the area of analysis in which electrochemistry has had the biggest impact on society is in biosensors, notably the glucose biosensor [48], Although Volume 9 is concerned with bioelectrochemistry, it is important that this area of electroanalytical chemistry is represented appropriately in Volume 3. Consequently, Schuhmann and Bonsen provide an overview of the physical principles and appKcations of biosensors in Chapter 2.11. A comprehensive overview is given of amperometric, potentiometric, conducti-metric and impedimetric formats for biosensors, and the relative merits of each are fully assessed. Potential new directions are highlighted, particularly connected to miniaturization and multisensor array detection strategies. 

An older general review by Stefan et al. [2] considers mathematical modeling for data processing (including a variety of chemometric methods such as linear and nonlinear partial least squares, fuzzy neural networks, and multivariate analysis of variance), designs for electrochemical sensor arrays as well as applications in environmental, food and clinical analysis. Arrays of potentiometric ion-selective electrodes, piezoelectric crystal sensors, and voltammetric biosensors, as well as the electronic nose gas-phase sensor arrays are reviewed. 

A sensor array for monitoring indicators of mannnalian cell metabolic status has been reported by Pemberton et al. [33], and is based on both enzyme-modified elements and chemical sensors for temperature, pH, and dissolved oxygen. The array, fabricated in a silicon platform using MEMS technology, consists of five-well sensor strips with a multipotentiostat to switch between potentiometric and amperometric measurement modes. Screen-printed biosensors for glucose and lactate were grafted onto two of the weUs. The authors envision applications to cell culture and cytotoxicity studies. 

The typical potentiometric BioET utilizes a sensor array with one-enzyme biosensor, and additionally it incorporates ion ISEs to counterbalance interference presented by related ions. 

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